Highlander

Among humans for centuries, an immortal specie existed. Connor MacLeod is a member of this specie. Unaware of his powers, he is unable to explain his revival after his apparent death in a clan-fight in the 15th century. This convinces the superstitious villagers to stone him and drive him out of the village. He then encounters another one of his kind, Ramirez, who indoctrinates him in the ways of the immortals. The only way these "immortals" can die is by having their heads cut off. Given the credo that there can only be one, you can imagine a race where everyone tries to chop everyone else's head off. Of course, in such a race, there'll be factions, and MacLeod and Ramirez are one side battling the forces of evil immortals who want to take over the planet and wreak destruction on it.